Network backhaul systems and methods

ABSTRACT

An exemplary system includes a first mobile telephone switching office subsystem configured to receive and forward network traffic, a second mobile telephone switching office subsystem configured to receive and forward network traffic, and a hub router communicatively connected to the first and second mobile telephone switching office subsystems via at least one network backhaul connection. The hub router configured to establish at least one communication tunnel from the hub router to the first mobile telephone switching office subsystem and establish at least one backup communication tunnel from the hub router to the second mobile telephone switching office subsystem, wherein the at least one backup communication tunnel is pre-signaled as a backup to the at least one communication tunnel. Corresponding systems and methods are also disclosed.

RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 12/414,307 by Benjamin J. Parker, filed on Mar. 30, 2009, andentitled NETWORK BACKHAUL SYSTEMS AND METHODS, which is herebyincorporated by reference in its entirety.

BACKGROUND INFORMATION

Communication networks provide many people and organizations with accessto a variety of applications and services. For example, with theproliferation of wireless communication networks such as mobiletelephone networks, access to mobile communication applications andservices has become widely available.

As mobile telephone networks have advanced, more applications andservices have been made available over the mobile telephone networks,including applications and services that are increasingly bandwidthintensive. Increases in the number of applications and services, as wellas increases in the bandwidth requirements for the applications andservices available over mobile telephone networks have led networkoperators and service providers to seek additional advancements inmobile telephone network technologies to help support such applicationsand services. As a particular example, improvements to mobile telephonebackhaul networks linking edge sub-networks to core networks aredesirable to better support the increasing demands for bandwidthintensive mobile communication applications and services.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate various embodiments and are a partof the specification. The illustrated embodiments are merely examplesand do not limit the scope of the disclosure. Throughout the drawings,identical or similar reference numbers designate identical or similarelements.

FIG. 1 illustrates an exemplary network backhaul system.

FIG. 2 illustrates exemplary communication tunnels within the system ofFIG. 1.

FIG. 3 illustrates another exemplary network backhaul system.

FIG. 4 illustrates exemplary communication tunnels within the system ofFIG. 3.

FIG. 5 illustrates an exemplary communication path within the system ofFIG. 1.

FIG. 6 illustrates an exemplary network backhaul method.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Exemplary network backhaul systems and methods are described herein.

An exemplary system includes a mobile telephone switching officesubsystem having a first aggregation router and a second aggregationrouter, and a mobile telephone cell site router communicativelyconnected to the mobile telephone switching office subsystem via anetwork backhaul connection. The cell site router is configured toestablish at least one communication tunnel from the cell site router tothe first aggregation router over the network backhaul connection,establish at least one backup communication tunnel from the cell siterouter to the second aggregation router over the network backhaulconnection, detect at least one traffic forwarding failure associatedwith the communication tunnel, and redirect network backhaul trafficdirected to the first aggregation router via the communication tunnel tothe second aggregation router via the backup communication tunnel inresponse to the detected traffic forwarding failure. In certainembodiments, establishment of the backup communication tunnel includespre-signaling the backup communication tunnel as backup to thecommunication tunnel.

Another exemplary system includes a first mobile telephone switchingoffice subsystem and a second mobile telephone switching officesubsystem configured to receive and forward network traffic, and a hubrouter communicatively connected to the first and second mobiletelephone switching office subsystems and to a plurality of mobiletelephone cell site subsystems via at least one network backhaulconnection. The hub router is communicatively disposed between each ofthe first and second mobile telephone switching office subsystems andthe plurality of mobile telephone cell site subsystems. The hub routeris configured to establish at least one communication tunnel from thehub router to the first mobile telephone switching office subsystem,establish at least one backup communication tunnel from the hub routerto the second mobile telephone switching office subsystem, detect atleast one traffic forwarding failure associated with the communicationtunnel, and redirect network backhaul traffic directed to the firstmobile telephone switching office subsystem via the communication tunnelto the second mobile telephone switching office subsystem the backupcommunication tunnel in response to the detected traffic forwardingfailure. In certain embodiments, establishment of the backupcommunication tunnel includes pre-signaling the backup communicationtunnel as backup to the communication tunnel.

An exemplary method may include establishing a communication pathbetween a mobile telephone cell site router and a first aggregationrouter of a mobile telephone switching office subsystem, pre-signaling abackup communication path between the mobile telephone cell site routerand a second aggregation router of the mobile telephone switching officesubsystem, detecting a traffic forwarding failure associated with thecommunication path, and automatically redirecting network backhaultraffic directed to the first aggregation router via the communicationpath to the second aggregation router via the backup communication pathin response to the traffic forwarding failure. In certain embodiments,establishment of the backup communication path includes pre-signalingthe backup communication path as backup to the communication path.

In certain embodiments, the exemplary method further includesestablishing at least one other backup communication path between themobile telephone cell site router and a backup mobile telephoneswitching office subsystem, detecting a traffic forwarding failureassociated with the backup communication path, and automaticallyredirecting network backhaul traffic directed to the mobile telephoneswitching office subsystem via the communication path or the backupcommunication path to the backup mobile telephone switching officesubsystem via the other backup communication path in response to thetraffic forwarding failure associated with the backup communicationpath. In certain embodiments, the other backup communication path ispre-signaled as backup to the communication path and the backupcommunication path.

These and other exemplary embodiments of network backhaul systems andmethods will now be described in more detail with reference to theaccompanying drawings.

In some examples, one or more of the exemplary systems described hereinmay include or be implemented in any computing hardware and/orinstructions (e.g., software programs), or combinations of computinginstructions and hardware, configured to perform one or more of theprocesses described herein. In particular, it should be understood thatthe exemplary systems, or one or more components of the exemplarysystems, may be implemented on one physical computing device or may beimplemented on more than one physical computing device. Accordingly, theexemplary systems may include any one of a number of computing devicesemploying any of a number of computer operating systems.

One or more of the processes described herein may be implemented atleast in part as computer-executable instructions, i.e., instructionsexecutable by one or more computing devices, tangibly embodied in acomputer-readable medium. In general, a processor (e.g., amicroprocessor) receives instructions, from a computer-readable medium(e.g., from a memory, etc.), and executes those instructions, therebyperforming one or more processes, including one or more of the processesdescribed herein. Such instructions may be stored and transmitted usinga variety of known computer-readable media.

A computer-readable medium (also referred to as a processor-readablemedium) includes any medium that participates in providing data (e.g.,instructions) that may be read by a computer (e.g., by a processor of acomputer). Such a medium may take many forms, including, but not limitedto, non-volatile media and/or volatile media. Non-volatile media mayinclude, for example, optical or magnetic disks and other persistentmemory. Volatile media may include, for example, dynamic random accessmemory (“DRAM”), which typically constitutes a main memory. Common formsof computer-readable media include, for example, a floppy disk, aflexible disk, hard disk, magnetic tape, any other magnetic medium, aCD-ROM, DVD, any other optical medium, punch cards, paper tape, anyother physical medium with patterns of holes, a RAM, a PROM, an EPROM, aFLASH-EEPROM, any other memory chip or cartridge, or any other mediumfrom which a computing device can read.

Accordingly, each of the components of the exemplary systems describedherein may be implemented as hardware, computing instructions (e.g.,software) tangibly embodied on a computer-readable medium, or acombination of hardware and tangibly embodied computing instructionsconfigured to perform one or more of the processes described herein.

FIG. 1 illustrates an exemplary network backhaul system 100 (or simply“system 100”). In certain embodiments, system 100 may include or beimplemented in a communication network such as a mobile telephonenetwork. As shown in FIG. 1, system 100 may include a mobile telephonecell site (“MTCS”) subsystem 110 (“cell site subsystem 110”) and amobile telephone switching office (“MTSO”) subsystem 120 connected toone another by a network backhaul connection 125 (“connection 125”).Connection 125 may include and/or may be implemented over any suitablemedium or media capable of carrying communication signals between cellsite subsystem 110 and MTSO subsystem 120, including optical fiber,microwave, and/or other broadband media. Hence, connection 125 may carrynetwork traffic between cell site subsystem 110 and MTSO subsystem 120.

In particular, connection 125 may be used to transport network backhaultraffic between cell site subsystem 110 and MTSO subsystem 120. Forexample, within a context of a communications network such as a mobiletelephone network, cell site subsystem 110 may include or be part of anedge sub-network (e.g., a geographically distributed access network)from which network backhaul traffic may be transported upstream vianetwork backhaul connection 125 to MTSO subsystem 120.

MTSO subsystem 120 may be configured to receive and forward networktraffic, including receiving and forwarding network backhaul traffic.For example, network backhaul traffic may be received and forwardedupstream to one or more core and/or backbone network devices (e.g.,Public Switched Telephone Network (“PSTN”) devices). In this manner,MTSO subsystem 120 may connect a wireless voice call to the PSTN and/orother core or backbone network.

MTSO subsystem 120 may be configured to function as a centralized switchsupporting multiple cell site subsystems such as cell site subsystem110. As such, MTSO subsystem 120 may control operations of a mobiletelephone network, including, but not limited to, provisioning,connecting, monitoring, routing, handing off, and tearing downcommunication circuits, sessions, and services.

MTSO subsystem 120 may be located at a particular geographic location.For example, MTSO subsystem 120 may be housed at a mobile telephoneswitching office.

As shown in FIG. 1, MTSO subsystem 120 may include a multi-serviceprovisioning platform 130 (“MSPP 130”) and first and second aggregationrouters 140-1 and 140-2 (collectively “aggregation routers 140”). MSPP130 and aggregation routers 140, which may include or be implementedusing any suitable computing hardware, computing instructions (e.g.,software), or combination thereof, may be configured to perform one ormore operations on network traffic, including but not limited toforwarding, routing, and switching network traffic. MSPP 130 andaggregation routers 140 may perform such operations at one or morelayers associated with network traffic, including one or more OpenSystems Interconnection (“OSI”) Model layers.

MSPP 130 may be configured to provision one or more services, includingprovisioning network resources for use by the services. For example,MSPP 130 may be configured to provision bundled services for one or moresubscribers at various network layers (e.g., transport, switching, androuting layers of a network). MSPP 130 may be configured to steercommunication tunnels and network traffic to appropriate routers, suchas aggregation routers 140.

MSPP 130 may be configured to handle and/or terminate a range ofphysical interfaces, including, but not limited to optical interfaces(e.g., synchronous optical networking (“SONET”) interfaces and opticalcarrier level interfaces (e.g., OC-3, OC-12, OC-48, OC-192)), digitalsubscriber line (“DSL”) interfaces, asynchronous transfer mode (“ATM”)interfaces, and Ethernet interfaces (e.g., 10/100Base-T and gigabitEthernet interfaces), for example. In certain embodiments, MSPP 130 maybe configured to function as an add/drop multiplexer configured tomultiplex network traffic for various optical interfaces and/orprotocols (e.g., from SONET to OC-48 or OC-192).

Aggregation routers 140 may be configured to receive and forward networktraffic, including network backhaul traffic received from cell sitesubsystem 110. For example, network backhaul traffic may be received byan aggregation router 140 and selectively forwarded to a destinationsuch as a core and/or backbone network device. Examples of such coreand/or backbone network devices may include, but are not limited to,Class-5 switches, radio network controllers, and signaling gateways. Incertain embodiments, aggregation routers 140 may include or beimplemented on one or more multi-layer switches (“MLSs”) such as one ormore next generation MLSs (“ngMLSs”).

In certain embodiments, cell site subsystem 110 may include a mobiletelephone base station subsystem 150 (“base station subsystem 150”)configured to send and receive wireless communication signals to/fromone or more communication devices 155 located within a geographic cell160. Base station subsystem 150 may include one or more componentsconfigured to support sending and receiving wireless communicationsignals to/from communication devices 155 located within cell 160. Suchcomponents may include, but are not limited to, one or moretransmitters, receivers, transceivers, antennae (e.g., antenna 165),signal processors, and controllers.

Communication device 155 may include any device configured tocommunicate with base station subsystem 150 when located within cell160. Examples of communication devices 155 may include, but are notlimited to, wireless communication devices, mobile communication devices(e.g., mobile telephones such as cellular telephones), personal digitalassistants, computers (e.g., laptop computers), and vehicularcommunication devices.

Communications between communication device 155 and base stationsubsystem 150 may include bearer (e.g., voice, data, and/or media)and/or operation, administration, and maintenance (“OAM”) traffic. Anysuitable wireless communication signals, protocols, and/or technologiesmay be used for the communications. Examples of such communicationprotocols and technologies, include, but are not limited to, GlobalSystem for Mobile Communications (“GSM”) technologies (e.g., Long TermEvolution (“LTE”)), Code Division Multiple Access (“CDMA”) technologies,Time Division Multiple Access (“TDMA”) technologies, Short MessageService (“SMS”), Multimedia Message Service (“MMS”), Evolution DataOptimized Protocol (“EVDO”) (e.g., “1xEVDO”), radio frequency (“RF”)signaling technologies, radio transmission technologies (e.g., One TimesRadio Transmission Technology (“1xRTT”)), Transmission Control Protocol(“TCP”), Internet Protocol (“IP”), File Transfer Protocol (“FTP”),Hypertext Transfer Protocol (“HTTP”), Hypertext Transfer Protocol Secure(“HTTPS”), Session Initiation Protocol (“SIP”), Simple Object AccessProtocol (“SOAP”), Extensible Mark-up Language (“XML”) and variationsthereof, Simple Mail Transfer Protocol (“SMTP”), Real-Time TransportProtocol (“RTP”), User Datagram Protocol (“UDP”), and other suitablecommunications protocols and technologies.

Communications with base station subsystem 150 may provide communicationdevice 155 with access to one or more of a plurality of servicesprovided over a communication network such as a mobile telephonenetwork. Examples of such services include, but are not limited to,voice communication services (e.g., cellular telephone service and/orVoice over Internet Protocol (“VoIP”)), data services, text messagingservices (e.g., SMS), and media messaging services (e.g., MMS). Incertain examples, specific services provided over a communicationnetwork may correspond to specific communication technologies used todeliver those services. For instance, communications technologies suchas EVDO, 1xRTT, and LTE may support and/or be used to deliver specificservices (e.g., EVDO based services, 1xRTT based services, and LTE basedservices) to communication device 155 via a communication network.Accordingly, a user of communication device 155 (e.g., an end user suchas a subscriber to one or more services) may obtain access to one ormore services provided over a communication network.

Cell site subsystem 110 may further include a cell site router 170,which may include or be implemented using any suitable computinghardware, computing instructions (e.g., software), or combinationthereof. Cell site router 170 may be physically deployed withingeographic cell 160 in certain embodiments.

Cell site router 170 may be configured to perform one or more operationson network traffic, including but not limited to forwarding, routing,and switching network traffic. Cell site router 170 may perform suchoperations at one or more layers associated with network traffic,including one or more OSI Model layers. Exemplary operations of cellsite router 170 will be described further below.

Cell site router 170 may be connected to base station subsystem 150 by acell site connection 175. Cell site connection 175 may include and/ormay be implemented over any suitable medium or media capable of carryingcommunication signals between cell site router 170 and base stationsubsystem 150. In certain examples, cell site connection 175 may includea legacy cell site connection over a legacy medium, such as DS-1 overcopper wires, for example. In such examples, instead of a legacyconnection and/or medium extending beyond cell 160 and for terminationat MTSO subsystem 120, cell site router 170 may terminate the legacyconnection and/or medium within cell 160. Accordingly, broadbandconnections (e.g., network backhaul connection 125) may be deployed andused to connect cell site subsystem 110 to MTSO subsystem 120 withouthaving to upgrade legacy connections and/or media within cell 160.Hence, network backhaul connection 120 and cell site connection 175 maycomprise diverse connection technologies, and base station subsystem 150may continue to utilize a legacy communication connection, session, andor medium to transmit network backhaul traffic. This configuration mayprovide significant cost savings associated with conversions of legacybackhaul network links to broadband backhaul network links capable ofsupporting bandwidth intensive services and traffic.

In certain other examples, cell site connection 175 may include a nextgeneration communication connection over a broadband medium, such asEthernet over a broadband medium, for example. Such a connection mayalso be terminated by cell site router 170. As described further below,connection 125 and one or more communication tunnels carried overconnection 125 may be configured to support various communicationprotocols and technologies, including legacy and next generationcommunication protocols and technologies. Accordingly, base stationsubsystems utilizing diverse backhaul communication technologies (e.g.,legacy and next generation communication technologies) may be connectedto a cell site router 170.

In certain embodiments, base station subsystem 150 may be configured toutilize multi-link point-to-point protocol (“MLPPP”) to encapsulatenetwork backhaul traffic (e.g., Internet Protocol (“IP) payloads) fortransmission to cell site router 170. Instead of base station subsystem150 transmitting such traffic directly to MTSO subsystem 120 over abackhaul link as may be done in legacy backhaul networks, the trafficfrom base station subsystem 150 may be transmitted to the cell siterouter 170 terminating cell site connection 175 in cell 160. Cell siterouter 170 may then control how network backhaul traffic is processedand transmitted over connection 125 independently of a particularnetwork backhaul protocol, medium, and/or technology used by basestation subsystem 150.

As shown in FIG. 1, cell site router 170 may be connected to MTSOsubsystem 120 via network backhaul connection 125. Accordingly,connection 125 may be used to carry network traffic between cell siterouter 170 and MTSO subsystem 120, including carrying network backhaultraffic from the cell site router 170 within cell 160 to MTSO subsystem120. Thus, base station subsystem 150 may transmit network backhaultraffic to cell site router 170 via cell site connection 175, and cellsite router 170 may transmit corresponding network backhaul traffic toMTSO subsystem 120 via network backhaul connection 125.

Cell site router 170 may be configured to establish one or morecommunication tunnels over connection 125 for use in carrying networktraffic between the cell site router 170 and MTSO subsystem 120. Incertain embodiments, for example, cell site router 170 may be configuredto establish at least one communication tunnel from the cell site router170 to aggregation router 140-1 and at least one backup communicationtunnel from the cell site router 170 to aggregation router 140-2 overnetwork backhaul connection 125.

FIG. 2 illustrates exemplary communication tunnels 210-1 and 210-2(collectively “communication tunnels 210”) established by the cell siterouter 170 within system 100. As shown in FIG. 2, communication tunnel210-1 may form a communication path between cell site router 170 andaggregation router 140-1 and communication tunnel 210-2 may form acommunication path between cell site router 170 and aggregation router140-2.

Communication tunnel 210-2 may be established as a backup tocommunication tunnel 210-1. Accordingly, backup communication tunnel210-2 may be established to have properties at least substantiallysimilar to the properties of communication tunnel 210-1 such that backupcommunication tunnel 210-2 is capable of functioning as a backup tocommunication tunnel 210-1.

In certain embodiments, cell site router 170 may establish communicationtunnel 210-2 in response to establishment of communication tunnel 210-1.For example, cell site router 170 may signal aggregation router 140-1 toestablish communication tunnel 210-1 between the cell site router 170and aggregation router 140-1. Responsive to this establishment ofcommunication tunnel 210-1, cell site router 170 may pre-signalestablishment of communication tunnel 210-2 (e.g., pre-signalaggregation router 140-2 to establish communication tunnel 210-2)between the cell site router 170 and aggregation router 140-2 as abackup to communication tunnel 210-1. As used herein, “pre-signaling” acommunication tunnel (e.g., communication tunnel 210-2) may refer tosignaling that is performed to establish communication tunnel 210-2without association to (e.g., before existence of) a pending operationto transmit network traffic over communication tunnel 210-2.Accordingly, communication tunnel 210-2 may be established in advancesuch that it is available for, and configured to support a future,substantially hitless transition and redirection of network traffic fromcommunication tunnel 210-1 to backup communication tunnel 210-2.

A communication tunnel 210 may include a discrete communication linksuitable for transporting network traffic between endpoints (e.g., cellsite router 170 and MTSO subsystem 120). In certain embodiments, acommunication tunnel 210 may include a pseudowire connecting andconfigured to carry traffic associated with a native service between twoendpoints over a packet-switched network connection. As used herein, a“pseudowire” refers to a discrete type of communication link configuredto emulate a native service over a packet-switched network, includingany of the exemplary services disclosed above. Hence, in certainembodiments, communication tunnel 210-1 may include a pseudowire, andcommunication tunnel 210-2 may include a backup pseudowire pre-signaledas a backup to the pseudowire. In certain embodiments, a communicationtunnel 210 may include a virtual circuit connecting two endpoints (e.g.,an Ethernet virtual circuit connecting cell site router 170 and MTSOsubsystem 120). In such embodiments, communication tunnel 210-1 mayinclude an Ethernet virtual circuit, and communication tunnel 210-2 mayinclude a backup Ethernet virtual circuit. In certain embodiments, acommunication tunnel 210 may include a pseudowire carried by an Ethernetvirtual circuit. In such embodiments, communication tunnel 210-1 mayinclude an Ethernet virtual circuit and at least one pseudowire carriedover the Ethernet virtual circuit, and communication tunnel 210-2 mayinclude a backup Ethernet virtual circuit and at least one backuppseudowire carried over the backup Ethernet virtual circuit.

In certain examples, cell site router 170 may establish a plurality ofpseudowires between the cell site router 170 and aggregation router140-1. Each of the pseudowires may correspond to a different one of aplurality of services provided over a communication network such as amobile telephone network. For example, separate pseudowires maybeestablished for EVDO, 1xRTT, and LTE based services. In certainembodiments, the plurality of pseudowires may be carried by a singleEthernet virtual circuit between the cell site router 170 andaggregation router 140-1.

In response to the establishment of the plurality of pseudowires betweenthe cell site router 170 and aggregation router 140-1, cell site router170 may pre-signal aggregation router 140-2 to establish a plurality ofcorresponding backup pseudowires between the cell site router 170 andaggregation router 140-2 as backup to the plurality of pseudowiresbetween the cell site router 170 and aggregation router 140-1.

Cell site router 170 and one or more elements of MTSO subsystem 120 maybe configured to establish communication tunnels 210 and to process(e.g., forward) network traffic using one or more suitable networkcommunication technologies. In certain embodiments, multi-protocol labelswitching (“MPLS”) may be used for processing network traffictransported or to be transported over a communication tunnel 210. Hence,the communication tunnel 210 may form an MPLS communication path. Insome embodiments, cell site router 170 may be configured to establish orotherwise manage such an MPLS path using a Label Distribution Protocol(“LDP”). This is illustrative only as other MPLS management technologiesmay be used in other embodiments.

With an MPLS path established, network traffic may be transportedbetween the cell site router 170 and MTSO subsystem 120 via the MPLSpath. Cell site router 170 may be configured as a backhaul network edgerouter capable of adding MPLS labels to data packets to be transportedover an MPLS path. Accordingly, MPLS-labeled network traffic may betransported over the predefined MPLS path (e.g., a path formed by acommunication tunnel 210 such as a pseudowire and/or Ethernet virtualcircuit) without dependence on a particular type of traffic, transportmedium, or protocol. Accordingly, diverse types of services, protocols,media, and network traffic may be supported.

Cell site router 170 may be configured to detect communication failuresassociated with a communication tunnel 210. For example, cell siterouter 170 may be configured to detect at least one traffic forwardingfailure associated with communication tunnel 210-1. A traffic forwardingfailure may include any failure that prevents, or may potentiallyprevent, successful delivery of network traffic over a communicationtunnel 210. The error detection may be performed in any suitable wayusing any suitable technologies. In certain embodiments, for example,cell site router 170 may be configured to use Bidirectional ForwardingDetection (“BFD”) to detect communication errors associated withcommunication tunnel 210-1. To this end, cell site router 170 mayestablish a session between the cell site router 170 and aggregationrouter 140-1 over communication tunnel 210-1. Cell site router 170 maythen monitor for communication failures in accordance with one or morepredefined failure criteria. For example, failure criteria may include amaximum ping time period (e.g., a time within a range of 50-100milliseconds) and a threshold number of detected failures (e.g., threefailures).

When cell site router 170 detects at least one traffic forwardingfailure associated with communication tunnel 210-1 and satisfying thepredefined failure criteria, cell site router 170 may automaticallyredirect network backhaul traffic directed to aggregation router 140-1via communication tunnel 210-1 to aggregation router 140-2 via backupcommunication tunnel 210-2 in response to the traffic forwardingfailure. This transfer from communication tunnel 210-1 to communicationtunnel 210-2 may be hitless in some examples at least becausecommunication tunnel 210-2 has been established in advance as a backupto communication tunnel 210-1, as described above.

Cell site router 170 may be similarly configured to detect communicationfailures associated with one or more other communication tunnels 210,including backup communication tunnel 210-2.

FIG. 3 illustrates another exemplary network backhaul system 300 (“orsimply “system 300”). As shown in FIG. 3, system 300 may include a hubrouter 310 communicatively connected to each of a plurality of MTCSsubsystems 110 (e.g., MTCS subsystems 110-1, 110-2, and 110-3) via arespective network backhaul connection 125. Hub router 310 is alsocommunicatively connected to each of a plurality of MTSO subsystems 120(e.g., first and second MTSO subsystems 120-1 and 120-2) via arespective network backhaul connection 125. As shown in FIG. 3, hubrouter 310 may be communicatively disposed between the MTCS subsystems110-1, 110-2, and 110-3 and the MTSO subsystems 120-1 and 120-2.

The MTCS subsystems 110, network backhaul connections 125, and MTSOsubsystems 120-1 shown in FIG. 3 may be configured in any of the waysdescribed above. In particular, each of the MTCS subsystems 110-1 mayinclude a cell site router 170. In FIG. 3, MTCS subsystems 110-1, 110-2,and 110-3 include cell site routers 170-1, 170-2, and 170-3,respectively. Each of the cell site routers 170-1, 170-2, and 170-3 maybe communicatively connected to hub router 310 via a respectiveconnection 125.

In certain embodiments, the MTCS subsystems 110-1, 110-2, and 110-3, hubrouter 310, and MTSO subsystems 120-1 and 120-2 are located at and/orconfigured to serve geographically diverse locations. For example, eachof the MTCS subsystems 110-1, 110-2, and 110-3 may be located within adifferent geographic cell 160, and each of the MTSO subsystems 120-1 and120-2 may be located at a different geographic location (e.g.,geographically diverse mobile telephone switching offices). In certainembodiments, hub router 310 may be located at an intermediate geographiclocation (e.g., a co-location site) that is remote of the geographiccells 160 associated with MTCS subsystems 110-1, 110-2, and 110-3 and ofthe geographic locations of MTSO subsystems 120-1 and 120-2. In otherembodiments, hub router 310 may be located within a geographic cell 160associated with one of the MTCS subsystems 110-1, 110-2, and 110-3. Forexample, hub router 310 may be implemented in one of the MTCS subsystems110-1, 110-2, and 110-3.

Hub router 310, which may include or be implemented using any suitablecomputing hardware, computing instructions (e.g., software), orcombination thereof, may be configured to perform one or more operationson network traffic, including but not limited to aggregating,forwarding, routing, and switching network traffic. In particular, hubrouter 310 may be configured to aggregate network backhaul trafficreceived from cell site routers 170-1, 170-2, and 170-3 located atsubtended cell sites. Hub router 310 may perform such operations at oneor more layers associated with network traffic, including at one or moreOSI Model layers. In certain examples, hub router 310 may include one ormore multi-layer switches.

Cell site routers 170-1, 170-2, and 170-3 may each be configured toestablish at least one communication tunnel over a respective connection125 to the hub router 310. Cell site routers 170-1, 170-2, and 170-3 mayestablish the communications tunnels with hub router 310 in any of theways described above.

Hub router 310 may be configured to establish at least one communicationtunnel between the hub router 310 and each of the MTSO subsystems 120-1and 120-2. In certain embodiments, hub router 310 may be configured toestablish one or more communication tunnels from the hub router 310 toone or more aggregation routers 140-1 and 140-2 of a first MTSOsubsystem 120-1 and one or more communication tunnels from the hubrouter 310 to one or more aggregation routers 140-3 and 140-4 of asecond MTSO subsystem 120-2. The connection tunnels may be configured inany of the ways described above to carry network traffic (e.g., networkbackhaul traffic) between the respective cell site routers 170 and theMTSO subsystems 120 via the hub router 310.

FIG. 4 illustrates exemplary communication tunnels 410-1 through 410-7(collectively “communication tunnels 410”) established in system 300. Asshown in FIG. 4, communication tunnel 410-1 may form a communicationpath between cell site router 170-1 and hub router 310, communicationtunnel 410-2 may form a communication path between cell site router170-2 and hub router 310, and communication tunnel 410-3 may form acommunication path between cell site router 170-3 and hub router 310.The communication tunnels 410-1, 410-2, and 410-3 connecting cell siterouters 170-1, 170-2, and 170-3 with hub router 310 may be respectivelyestablished by cell site routers 170-1, 170-2, and 170-3 in any of theways described above.

As further shown in FIG. 4, communication tunnel 410-4 may form acommunication path between hub router 310 and a first aggregation router140-1 of MTSO subsystem 120-1, and communication tunnel 410-5 may form acommunication path between hub router 310 and a second aggregationrouter 140-2 of MTSO subsystem 120-1. Similarly, communication tunnel410-6 may form a communication path between hub router 310 and a firstaggregation router 140-3 of MTSO subsystem 120-2, and communicationtunnel 410-7 may form a communication path between hub router 310 and asecond aggregation router 140-4 of MTSO subsystem 120-2. Thecommunication tunnels 410-4, 410-5, 410-6, and 410-7 connecting hubrouter 310 with MTSO subsystems 120-1 and 120-2 may be established byhub router 310 in any of the ways described above, includingrespectively signaling and/or pre-signaling aggregation router 140-1,140-2, 140-3, and 140-4 to establish the communication tunnels 410-4,410-5, 410-6, and 410-7.

Hub router 310 may be configured to selectively associate one or more ofthe communication tunnels 410-1, 410-2, and 410-3 established betweencell site routers 170-1, 170-2, and 170-3 and hub router 310 with one ormore of the communication tunnels 410-4, 410-5, 410-6, and 410-7established between hub router 310 and MTSO subsystems 120-1 and 120-2to form one or more communication paths between cell site routers 170-1,170-2, and 170-3 and MTSO subsystems 120-1 and 120-2. For example, hubrouter 310 may associate communication tunnel 410-1 with communicationtunnel 410-4 to form a first communication path 420-1 between MTCSsubsystem 110-1 and MTSO subsystem 120-1. Additionally or alternatively,hub router 310 may associate communication tunnel 410-1 withcommunication tunnel 410-5 to form a second communication path 420-2between MTCS subsystem 110-1 and MTSO subsystem 120-1. Hub router 310may similarly associate communication tunnel 410-1 with communicationtunnel 410-6 to form communication path 420-3 between MTCS subsystem110-1 and MTSO subsystem 120-2. Additionally or alternatively, hubrouter 310 may associate communication tunnel 410-1 with communicationtunnel 410-7 to form a second communication path 420-4 between MTCSsubsystem 110-1 and MTSO subsystem 120-1. Communication paths 420-1,420-2, 420-3, and 420-4, which may be collectively referred to as“communication paths 420,” may comprise MPLS paths as described above.Hub router 320 may associate other sets of communications tunnels 410 toform similar communication paths between MTCS subsystems 110-2 and 110-3and MTSO subsystems 120-1 and 120-2.

One or more of the communication tunnels 410 and/or communication paths420 may be established as backup to one or more other communicationtunnels 410 and/or communication paths 420. For example, communicationtunnel 410-5 may be established as a backup to communication tunnel410-4. Accordingly, communication path 420-2 may be a backup tocommunication path 420-1. As another example, communication tunnel 410-7may be established as a backup to communication tunnel 410-6.Accordingly, communication path 420-4 may be a backup to communicationpath 420-3. As yet another example, communication tunnels 410-6 and410-7 may be established as backup to communication tunnels 410-4 and410-5. Accordingly, communication paths 420-3 and/or 420-4 may beestablished as backup to communication paths 420-1 and/or 420-2.

In certain embodiments, one or more backup communication tunnels 410and/or backup communication paths 420 may be established in response toestablishment of one or more other communication tunnels 410 and/orcommunication paths 420. For example, hub router 310 may signalaggregation router 140-1 to establish communication tunnel 410-4 betweenthe hub router 310 and aggregation router 140-1. Responsive to thisestablishment of communication tunnel 410-4, hub router 310 maypre-signal aggregation router 140-2 to establish communication tunnel410-5 between the hub router 310 and aggregation router 140-2 as backupto communication tunnel 410-4. Additionally or alternatively, responsiveto the establishment of communication tunnel 410-4, hub router 310 maypre-signal aggregation router 140-3 and/or aggregation router 140-4 toestablish communication tunnel 410-6 and/or communication tunnel 410-7between the hub router 310 and aggregation router 140-3 and/oraggregation router 140-4 as backup to communication tunnel 410-4.

A communication tunnel 410 may include any discrete communication linksuitable for transporting network traffic between endpoints (e.g.,between a cell site router 170 and the hub router 310 and/or between thehub router 410 and a MTSO subsystem 120). A communication tunnel 410 maybe configured in any of the ways described above in reference to acommunication tunnel 210. Hence, in certain embodiments, a communicationtunnel 410 may include one or more pseudowires and/or one or morevirtual circuits (e.g., Ethernet virtual circuits) connecting twoendpoint devices and configured to carry traffic associated with one ormore native services over a packet-switched network connection.

Hub router 310 may be configured to detect one or more communicationfailures associated with communication tunnels 410-4, 410-5, 410-6,and/or 410-7. For example, hub router 310 may be configured to detect atleast one traffic forwarding failure associated with communicationtunnel 410-4. The error detection may be performed in any suitable wayusing any suitable technologies. In certain embodiments, hub router 310may be configured to use BFD to detect communication errors associatedwith communication tunnel 410-4. To this end, hub router 310 mayestablish a session between the hub router 310 and aggregation router140-1 over communication tunnel 410-4. Hub router 310 may then monitorfor communication failures in accordance with one or more predefinedfailure criteria, including any of the exemplary failure criteriadescribed above.

When hub router 310 detects at least one traffic forwarding failureassociated with communication tunnel 410-4 and satisfying the predefinedfailure criteria, hub router 310 may automatically redirect networkbackhaul traffic directed to aggregation router 140-1 via communicationtunnel 410-4 to a backup device over a backup communication tunnel. Forexample, hub router 310 may automatically redirect network backhaultraffic directed to aggregation router 140-1 via communication tunnel410-4 to aggregation router 140-2 via backup communication tunnel 410-5in response to the traffic forwarding failure. This transfer fromcommunication tunnel 410-4 to communication tunnel 410-5 may besubstantially hitless in some examples at least because communicationtunnel 410-5 has been established in advance as backup to communicationtunnel 410-4.

Hub router 310 may be configured to detect a communication failure withan MTSO subsystem 120. The error detection may be performed in any ofthe ways described above, including using BFD to detect communicationerrors that satisfy predefined criteria and are associated withcommunication tunnels 410 terminated at the MTSO subsystem 120.

As an example, hub router 310 may detect traffic forwarding errorsassociated with communication tunnels 410-4 and 410-5 and satisfying thepredefined failure criteria. For instance, hub router 310 may detect afirst traffic forwarding failure associated with communication tunnel410-4 and a second traffic forwarding failure associated withcommunication tunnel 410-5. Based on the detected errors, hub router 310may identify a complete communication failure with MTSO subsystem 120-1.In response, hub router 310 may automatically redirect network backhaultraffic directed to MTSO subsystem 120-1 to MTSO subsystem 120-2 via atleast one of communication tunnels 410-6 and 410-7. This transition fromone or more communication tunnels 410-4 and 410-5 terminated at MTSOsubsystem 120-1 to one or more communication tunnels 410-6 and 410-7 maybe substantially hitless in some examples at least because communicationtunnels 410-6 and 410-6 have been pre-signaled and established inadvance as backup to communication tunnels 410-4 and 410-5 terminated atMTSO subsystem 120-1. Accordingly, MTSO subsystem 120-2 may function asa geographically diverse backup to MTSO subsystem 120-1.

In certain embodiments, network backhaul traffic may be load balancedover multiple communication tunnels. In system 300, for example, hubrouter 310 may be configured to load balance network backhaul trafficbetween MTSO subsystems 120-1 and 120-2. Additionally or alternatively,hub router 310 may be configured to load balance network backhaultraffic between multiple aggregation routers 140 of an MTSO subsystem120 (e.g., between aggregation routers 140-1 and 140-2 of MTSOsubsystems 120-1). As another example, in system 100, cell site router170 may be configured to load balance network backhaul traffic betweenaggregation routers 140-1 and 140-2 of MTSO subsystem 120.

As mentioned above, an MTSO subsystem 120 may be configured to controloperations of a mobile telephone network, including provisioning,connecting, monitoring, routing, handing off, and tearing downcommunication circuits, sessions, and services associated with cellsites served by the MTSO subsystem 120. In certain exemplaryembodiments, one or more of such control operations may be offloadedfrom the MTSO subsystem 120. In certain examples, such offloading mayhelp reduce latency, alleviate congestion, and improve performanceassociated with network backhaul traffic.

For example, in certain embodiments, hub router 310 may be configured tobreak out select network traffic for management by the hub router 310.As used herein, a “break out” of select network traffic by hub router310 may comprise a redirection of select network traffic downstream suchthat the select network traffic is not forwarded upstream to either ofMTSO subsystems 120-1 or 120-2. Hub router 310 may be configured toestablish one or more communication tunnels and/or communication pathsto support a break out of select network traffic for management by hubrouter 310.

As an example, in system 300, hub router 310 may be configured tocontrol certain operations associated with select network traffic of amobile telephone network, while MTSO subsystems 120-1 and/or 120-2control operations associated with other network traffic. In particular,hub router 310 may be configured to break out network traffic associatedwith endpoint devices located exclusively within the one or more of thegeographic cell 160 associated with MTCS subsystems 110 subtended to hubrouter 310.

For instance, a subscriber to a wireless voice communication service mayuse a communication device 155 located within a geographic cell 160served by MTCS subsystem 110-1 to initiate a voice call directed toanother subscriber associated with another communication device 155located within another geographic cell 160 served by MTCS subsystem110-2. Hub router 310 may receive a voice call request from MTCSsubsystem 110-1 and determine that the requested voice call is to bebetween communication devices 155 located within geographic cells 160served by MTCS subsystems 110-1 and 110-2, which are both subtended toand served by hub router 310. In response, rather than forward therequest upstream to one of the MTSO subsystem 120-1 and 120-2, hubrouter 310 may take control of signaling to establish a communicationpath between MTCS subsystem 110-1 and MTCS subsystem 110-2 to be usedfor the requested voice call. The hub router 310 may then break outnetwork traffic associated with the voice call (e.g., voice bearertraffic) for transport over the communication path between MTCSsubsystem 110-1 and MTCS subsystem 110-2. Accordingly, hub router 310may perform a breakout of select network traffic closer to one or moreedges of a mobile telephone network and thereby reduce network trafficto/from MTSO subsystems 120-1 and/or 120-2.

FIG. 5 illustrates an exemplary network communication path 505controlled and managed by hub router 310 rather than by MTSO subsystem120-1 or 120-2 in system 300. Communication path 505 may be formed by afirst communication tunnel 510 providing a communication link betweencell site subsystem 110-1 and hub router 310 and a second communicationtunnel 510 providing a communication link between hub router 310 andcell site subsystem 110-2. Hub router 310 may be configured to establishand associate communications tunnel 510 and 520 with one another in anyof the ways described herein to form communication path 505. Hub router310 may then break out select network traffic for transport over thecommunication path 505.

In other embodiments, MTSO subsystem 120-1 and/or 120-2 may stillcontrol signaling to establish communication path 505 for such a voicecall, and hub router 310 may be configured to take over control of thecommunication path 505 after the path 505 has been established and/or tobreak out select network traffic for transport over the communicationpath 505.

In certain embodiments, hub router 310 may be configured to use MPLSlabels to selectively breakout select network traffic. As describedabove, cell site routers 170 may be configured to append MPLS labels tonetwork backhaul traffic. Hub router 310 may be configured to identifyfrom the MPLS labels select traffic that may be broken out at the hubrouter 310.

Any suitable computing hardware, computing instructions (e.g.,software), or combination thereof, may be implemented at hub router 310and used to support breakout of select traffic at the hub router 310 asdescribed above. For example, hub router 310 include one or moreswitches (e.g., a MLS), gateways, and/or other network elements,including, but not limited to, a system architecture evolution (“SAE”)gateway, mobility management entity (“MME”), serving gateway (“S-GW”),MSPP, and/or Packet Data Network (“PDN”) gateway.

FIG. 6 illustrates an exemplary network backhaul method. While FIG. 6illustrates exemplary steps according to one embodiment, otherembodiments may omit, add to, reorder, and/or modify any of the stepsshown in FIG. 6. In certain embodiments, a cell site router 170 and/orhub router 310 may perform one or more of the steps shown in FIG. 6.

In step 610, a communication path between a mobile telephone cell siterouter and a first aggregation router of an MTSO subsystem isestablished. Step 610 may be performed in any of the ways describedabove, including by the mobile telephone cell site router (e.g., cellsite router 170) and/or hub router 310 signaling the first aggregationrouter (e.g., aggregation router 140-1) to establish the communicationpath.

In certain embodiments, the communication path established in step 610may comprise a single communication tunnel (e.g., communication tunnel210-1) between the mobile telephone cell site router and the firstaggregation router of the MTSO subsystem. In other embodiments, thecommunication path established in step 610 may comprise a firstcommunication tunnel (e.g., communication tunnel 410-1) between themobile telephone cell site router and hub router 310 and a secondcommunication tunnel (e.g., communication tunnel 410-4) between hubrouter 310 and the first aggregation router of the MTSO subsystem. Insuch embodiments, hub router 310 may be communicatively disposed betweenand connected to the mobile telephone cell site router and the MTSOsubsystem and may be configured to associate the first communicationtunnel with the second communication tunnel to form the communicationpath, as described above.

In step 620, a backup communication path between the mobile telephonecell site router and a second aggregation router of the MTSO subsystemis pre-signaled. The backup communication path may be established in anyof the ways described above. For example, the backup communication pathmay be pre-signaled as backup to the communication path established instep 610. The pre-signaling may be performed by a cell site router 170and/or hub router 310 in any of the ways described above.

In certain embodiments, the backup communication path pre-signaled instep 620 may comprise a single communication tunnel (e.g., communicationtunnel 210-2) between the mobile telephone cell site router and thesecond aggregation router of the MTSO subsystem. In other embodiments,the backup communication path pre-signaled in step 620 may comprise afirst communication tunnel (e.g., communication tunnel 410-1) betweenthe mobile telephone cell site router and hub router 310 and a secondcommunication tunnel (e.g., communication tunnel 410-5) between hubrouter 310 and the second aggregation router of the MTSO subsystem. Insuch embodiments, hub router 310 may be configured to associate thefirst communication tunnel with the second communication tunnel to formthe backup communication path, as described above.

In step 630, a traffic forwarding failure associated with thecommunication path established in step 610 is detected. Step 630 may beperformed in any of the ways described above, including a cell siterouter 170 and/or hub router 310 using BFD to detect the trafficforwarding failure.

In step 640, network backhaul traffic directed to the first aggregationrouter via the communication path established in step 610 isautomatically redirected to the second aggregation router via the backupcommunication path pre-signaled in step 620. Step 640 may be performedin any of the ways described above and in response to the detectedtraffic forwarding failure.

In step 650, at least one other backup communication path ispre-signaled between the mobile telephone cell site router and a backupMTSO subsystem. The other backup communication path(s) (e.g.,communication paths 420-3 and 420-4) may be pre-signaled in any of theways described above. For example, the backup communication path(s) maybe pre-signaled as backup to the communication path established in step610 and/or the backup communication path pre-signaled in step 620. Thepre-signaling may be performed by hub router 310 in any of the waysdescribed above.

In step 660, a traffic forwarding failure associated with the backupcommunication path pre-signaled in step 620 is detected. Step 660 may beperformed in any of the ways described above, including hub router 310using BFD to detect the traffic forwarding failure.

In step 670, network backhaul traffic directed to the MTSO subsystem viathe communication path established in step 610 or the backupcommunication path pre-signaled in step 620 is automatically redirectedto the backup MTSO subsystem via at least one of the other backupcommunication paths pre-signaled in step 650. Step 670 may be performedin any of the ways described above and in response to the detectedtraffic forwarding failure associated with the backup communication pathpre-signaled in step 620.

In the preceding description, various exemplary embodiments have beendescribed with reference to the accompanying drawings. It will, however,be evident that various modifications and changes may be made thereto,and additional embodiments may be implemented, without departing fromthe scope of the invention as set forth in the claims that follow. Forexample, certain features of one embodiment described herein may becombined with or substituted for features of another embodimentdescribed herein. The description and drawings are accordingly to beregarded in an illustrative rather than a restrictive sense.

1. A system comprising: a first mobile telephone switching officesubsystem and a second mobile telephone switching office subsystemconfigured to receive and forward network traffic; a hub routercommunicatively connected to said first and second mobile telephoneswitching office subsystems and to a plurality of mobile telephone cellsite subsystems via at least one network backhaul connection, said hubrouter communicatively disposed between each of said first and secondmobile telephone switching office subsystems and said plurality ofmobile telephone cell site subsystems, said hub router configured toestablish at least one communication tunnel from said hub router to saidfirst mobile telephone switching office subsystem, establish at leastone backup communication tunnel from said hub router to said secondmobile telephone switching office subsystem, detect at least one trafficforwarding failure associated with said at least one communicationtunnel, and redirect network backhaul traffic directed to said firstmobile telephone switching office subsystem via said at least onecommunication tunnel to said second mobile telephone switching officesubsystem via said at least one backup communication tunnel in responseto said at least one traffic forwarding failure.
 2. The system of claim1, wherein said at least one backup communication tunnel is pre-signaledas backup to said at least one communication tunnel.
 3. The system ofclaim 2, wherein said redirection of said network backhaul trafficcomprises a substantially hitless transition from said at least onecommunication tunnel to said at least one backup communication tunnel.4. The system of claim 1, wherein: said first mobile telephone switchingoffice subsystem comprises a first aggregation router and a secondaggregation router; said at least one communication tunnel comprises afirst communication tunnel between said hub router and said firstaggregation router and a second communication tunnel between said hubrouter and said second aggregation router; and said hub router isconfigured to establish said second communication tunnel as a backup tosaid first communication tunnel.
 5. The system of claim 4, wherein saiddetection of said at least one traffic forwarding failure associatedwith said at least one communication tunnel comprises a detection of afirst traffic forwarding failure associated with said firstcommunication tunnel between said hub router and said first aggregationrouter and a second traffic forwarding failure associated with saidsecond communication tunnel between said hub router and said secondaggregation router.
 6. The system of claim 1, wherein said hub router isconfigured to break out select network traffic for management by saidhub router.
 7. The system of claim 1, wherein said mobile telephone cellsite subsystem comprises: a base station configured to communicate withat least one communication device located within a geographic cell byway of wireless communication signals; and a cell site routercommunicatively connected to said base station and configured toestablish at least one communication tunnel between said cell siterouter and said hub router; wherein said hub router is configured toassociate said at least one communication tunnel between said cell siterouter and said hub router with said at least one communication tunnelbetween said hub router and said first mobile telephone switching officesubsystem to form a communication path between said cell site router andsaid first mobile telephone switching office subsystem.
 8. A systemcomprising: a first mobile telephone switching office subsystemconfigured to receive and forward network traffic; a second mobiletelephone switching office subsystem configured to receive and forwardnetwork traffic; and a hub router communicatively connected to saidfirst and second mobile telephone switching office subsystems via atleast one network backhaul connection, said hub router configured toestablish at least one communication tunnel from said hub router to saidfirst mobile telephone switching office subsystem, and establish atleast one backup communication tunnel from said hub router to saidsecond mobile telephone switching office subsystem, wherein said atleast one backup communication tunnel is pre-signaled as a backup tosaid at least one communication tunnel.
 9. The system of claim 8,wherein the hub router is further configured to detect at least onetraffic forwarding failure associated with said at least onecommunication tunnel, and redirect network backhaul traffic directed tosaid first mobile telephone switching office subsystem via said at leastone communication tunnel to said second mobile telephone switchingoffice subsystem via said at least one backup communication tunnel inresponse to said at least one traffic forwarding failure.
 10. The systemof claim 9, wherein said redirection of said network backhaul trafficcomprises a substantially hitless transition from said at least onecommunication tunnel to said at least one backup communication tunnel.11. The system of claim 9, wherein: said first mobile telephoneswitching office subsystem comprises a first aggregation router and asecond aggregation router; said at least one communication tunnelcomprises a first communication tunnel between said hub router and saidfirst aggregation router and a second communication tunnel between saidhub router and said second aggregation router; and said hub router isconfigured to establish said second communication tunnel as a backup tosaid first communication tunnel.
 12. The system of claim 11, whereinsaid second communication tunnel is pre-signaled as a backup to saidfirst communication tunnel.
 13. The system of claim 11, wherein saiddetection of said at least one traffic forwarding failure associatedwith said at least one communication tunnel comprises a detection of afirst traffic forwarding failure associated with said firstcommunication tunnel between said hub router and said first aggregationrouter and a second traffic forwarding failure associated with saidsecond communication tunnel between said hub router and said secondaggregation router.
 14. The system of claim 8, wherein: said hub routeris communicatively connected to a plurality of mobile telephone cellsite subsystems; and said hub router is communicatively disposed betweeneach of said first and second mobile telephone switching officesubsystems and said plurality of mobile telephone cell site subsystems.15. The system of claim 8, wherein: said at least one communicationtunnel comprises a plurality of pseudowires; and each of saidpseudowires is dedicated to a different one of a plurality of servicesprovided over a mobile telephone network.
 16. The system of claim 15,wherein said plurality of services comprises an Evolution Data Optimized(“EVDO”) based service, a Long Term Evolution based (“LTE”) service, anda One Times Radio Transmission Technology (“1xRTT”) based service. 17.The system of claim 15, wherein said at least one backup communicationtunnel comprises a plurality of backup pseudowires pre-signaled asbackup to said plurality of pseudowires.
 18. The system of claim 8,wherein said at least one communication tunnel comprises an Ethernetvirtual circuit and at least one pseudowire carried over said Ethernetvirtual circuit, and said at least one backup communication tunnelcomprises a backup Ethernet virtual circuit and at least one backuppseudowire carried over said backup Ethernet virtual circuit.
 19. Amethod comprising: establishing at least one communication path betweena mobile telephone cell site router and a first mobile telephoneswitching office subsystem; pre-signaling at least one backupcommunication path between said mobile telephone cell site router and asecond mobile telephone switching office subsystem; detecting a trafficforwarding failure associated with said at least one communication pathbetween said mobile telephone cell site router and said first mobiletelephone switching office subsystem; and redirecting network backhaultraffic directed to said first mobile telephone switching officesubsystem via said at least one communication path to said second mobiletelephone switching office subsystem via said at least one backupcommunication path in response to said traffic forwarding failure. 20.The method of claim 19, wherein said establishing said at least onecommunication path between said mobile telephone cell site router andsaid first mobile telephone switching office subsystem comprises:establishing a communication tunnel between said mobile telephone cellsite router and a hub router communicatively disposed between saidmobile telephone cell site router and said first mobile telephoneswitching office subsystem; establishing at least one othercommunication tunnel between said hub router and said first mobiletelephone switching office subsystem; and said hub router associatingsaid communication tunnel and said at least one other communicationtunnel to form said at least one communication path.
 21. The method ofclaim 19, wherein said pre-signaling said at least one backupcommunication path between said mobile telephone cell site router andsaid second mobile telephone switching office subsystem comprises:pre-signaling at least one backup communication tunnel between said hubrouter and said second mobile telephone switching office subsystem; andsaid hub router associating said communication tunnel and said at leastone backup communication tunnel to form said at least one backupcommunication path.
 22. The method of claim 19, wherein: said at leastone communication path comprises at least one Multi-Protocol LabelSwitching (“MPLS”) path; and said at least one backup communication pathcomprises at least one other Multi-Protocol Label Switching (“MPLS”)path.
 23. The method of claim 19, tangibly embodied ascomputer-executable instructions on at least one non-transitorycomputer-readable medium.